HERE Map Tile v2 Developer's Guide

Frequently asked questions

Frequently Asked Questions about the HERE Map Tile v2.

How do I request the right info?

You always need to query the info resource of the same Base URL you are using.

Example: If you are using map tiles from the Base Map Tile Resources pool, you should query the info page of that same URL. In other words, if you are creating requests as follows:

https://1.base.maps.ls.hereapi.com
  /maptile/2.1/maptile/newest/normal.day/13/4400/2686/256/png8
?apiKey={YOUR_API_KEY}

You need to query the info page as follows:

https://1.base.maps.ls.hereapi.com
  /maptile/2.1/info
?apiKey={YOUR_API_KEY}

Note: These examples use a HERE API Key to authenticate your request. For the available authentication options, see the Identity & Access Management Developer Guide.

For more details, see Map Versions.

If you use different map tile resources, you need to query all URLs separately as they contain different information.

How do I request the right copyright information?

You always need to query the copyright resource of the same Base URL you are using.

Example: If you are using map tiles from the Base Map Tile Resources pool, you should query the copyright page of that same URL. In other words, if you are creating requests as follows:

https://1.base.maps.ls.hereapi.com/maptile/2.1/maptile/newest/normal.day/13/4400/2686/256/png8
?apiKey={YOUR_API_KEY}

You need to query the copyright page as follows:

https://1.base.maps.ls.hereapi.com/maptile/2.1/copyright/newest
?apiKey={YOUR_API_KEY}

Note: These examples use a HERE API Key to authenticate your request. For the available authentication options, see the Identity & Access Management Developer Guide.

If you use different map tile resources, you need to query all URLs separately as they may contain different copyright information.

How do I calculate the distance to the ground depending on the zoom level?

When using a Mercator Projection on a tile based system, it is better to talk about how many meters a pixel represents rather than to calculate the scale of the map at a certain zoom level.

Please remember that due to the limitations of Mercator Projection the ordinate y becomes infinite at the poles and the map must be truncated at some latitude less than ninety degrees. This needs to be done symmetrically. Our map is truncated at 80ºN and 66ºS with the result that European countries are moved towards the center of the map.

For example, at zoom level 0 where the whole world consists of a single tile 256 pixels wide, we can calculate meters by pixel (m/px) using an Earth radius of 6378.137km as 156,543.03 That would yield an approximated scale of 1:500 Mill. (taking the scale as an approximate size comparison referring to distances on the equator), as the map scale will depend on the monitor we have used a monitor with a 0.3 mm / pixel.

Here is a table with approximated values for the zoom level correspondence to scale.

zoom level	scale (m/pixel)
0	156,543.03
1	78,271.52
2	39,135.76
3	19,567.88
4	9,783.94
5	4,891.97
6	2,445.98
7	1,222.99
8	611.50
9	305.75
10	152.87
11	76.44
12	38.22
13	19.11
14	9.55
15	4.78
16	2.39
17	1.19
18	0.60
19	0.30
20	0.15

Nevertheless, you can use a formula to calculate the meters per pixel for 256 pixel tiles. The distance represented by one pixel (S) is given by:

S=C*cos(y)/2^(z+8)

where:

C is the equatorial circumference of the Earth

z is the zoom level

y is the latitude of where you are interested in the scale in degrees

Since the Earth is actually ellipsoidal, there will be a slight error in this calculation (0.3% maximum)

How do I know if a particular resource is available?

You can always use the info page resource to query if a particular tile type or scheme is available in the map tile resource URL you choose.